Lock and seal for screws



July 17, 1928. 1,667,607"

F. H. WOOD LOCK AND SEAL FOR SCREEWS Filed sept. 24, 1926 'WfiwINVENTOR.

mm 242M Patented July 17, 1928.

UNITED STATES PATENT OFFICE.

FREDERICK H. WOOD, OF CHICAGO, ILLINOIS.

LOCK AND SEAL FOR SCREWS.

Application filed September %4, 1926. Serial No. 139,567.

The screw being first driven, when the staple is driven home theprojection formed by the head of the staple will engage the slot of thescrew forcing the humps on the prongs to engage the undercut wall of thescrew. The head of the staple binding in the slot of the screw, and thehumps engaging the under cut wall of the screw, makes it impos-' sibleto remove the staple without mutilating the material into which thescrew and staple have been driven; and as the head of the staple fillsthe slot of the screw, a screw driver cannot be used until the staplehas been removed. The staple therefore forms a lock for the screw, toprevent its removal or its working loose. It also forms a seal in thatit cannot be removed without an indication that it has been tamperedwith.

The purpose of this invention is to prevent pilfering from packages intransit and to prevent the removal of screws generally wherever it isdesirable to protect them, and to prevent screws working loose. It isintended particularly with screws designed to be driven like nails andthen turned with a screw driver to make them hold firmly.

Having described the purpose of my invention the nature-of the same willbe fully understood from the description I give below, when consideredin connection with the 7 the screw, before the staple hasbeen drivenbeyond the bend. Figure 3 represents a modified form of staple intendedfor the larger screws, in the position it would 00- cupy after the screwand the staple have been driven. Figure 4 shows the same staple as ofFigure 3 before it is entirely driven.

In Figure 1 A is a standard screw with the usual cross slot B andundercut wall of the periphery of the screw hea'd G. D is one of twoprongs of the staple extending at an angle from its head, the prongshaving a bend or hump at E and the head forming a projection on the sideopposite from the hump.

Figure 2 is intended to show that when the staple is fully driven, beingformed of spring metal it will either force the wood,

permitting the staple to occupy its position as of igure 1, or itsresilience will cause it to b1nd 1n the slot of the-screw;

In Figures 3 and 4, the modified form of staple, I) has. a hump F whichon entering the slot because of the undercut periphery of the screwhead, reaches a point where it is clear of the screw, and as the stapleis driven until the projection G enters the slot, the staple is forcedover until the hump engages the under cut periphery of the screw head 7at C.

Staples such as these indicated may be used where metal is screwed ontowood or where the screw is driven into metal, holes being drilled forthe staple, and the hump made at such position on the prong of thestaple as to meet the requirement, the spring metal of the staplebinding the staple in the slot of the screw.

I claim A staple for use in connection with a standard screw head withthe usual cross slot and under cut periphery, comprising a head adaptedto fit snugly into the cross slot, and prongs extending at an angletherefrom through the ends of said slot, each of said prongs having ahump on one side, and said head forming a projection on the oppositeside, the projection forcing the hump into engagement with the undercutwall of the screw head.

FREDERICK H. WOOD.

